method remove

Source

void remove(Animatable animatable) {
  if (animatable != null) {
    var link = _firstAnimatableLink;
    while (identical(link, _lastAnimatableLink) == false) {
      if (identical(link.animatable, animatable)) {
        link.animatable = null;
        break;
      }
      link = link.nextAnimatableLink;
    }
  }
}